The problem of False Answer Supervision (FAS) has plagued the telecommunications industry for years. FAS generally refers to the fraudulent handling of phone calls within one of the PSTN (Public Switched Telephone Network) branches of a phone call made over a PSTN-VOIP-PSTN network, and at that, typically within the recipient PSTN branch of the call path. The fraudulent conduct may include deliberately billing for a period of time in excess of the actual call duration, billing for calls not normally eligible for billing such as calls in which the intended recipient is outside of a service area and calls that are directed to voice mail. Other fraudulent acts include having an FAS service reroute customer traffic to an IVR (Interactive Voice Response system) or send back a false ring back tone and charge customers high-cost destinations and thereby make a huge profit in the process.
To date, approaches for detecting FAS have been based on the use of CDR (Call Data Records) alone. When call durations go down on average, and completion ratios increase, this means a lot of calls are being completed for a very short duration. This, in turn, indicates callers are being routed to an IVR, which answers essentially every call, but callers are also hanging up quickly after realizing they have not reached the party they intended to call.
Using CDR by itself is not particularly effective, and can lead to false positive detections (that is, incorrect determinations that carriers are practicing FAS). Accordingly, there is a need in the art for improved systems and methods for detecting and responding to FAS activity by carriers.